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Injured or ischemic cardiac tissue has limited intrinsic capacity for regeneration. While stem cell transplantation is a promising approach to stimulating cardiac repair, its success in humans has thus far been limited. Harnessing the therapeutic benefits of stem cells requires a better understanding of their mechanisms of action and methods to optimize their function. Cardiac stem cells (CSC) represent a particularly effective cellular source for cardiac repair, and pre-conditioning CSC with electrical stimulation (EleS) was demonstrated to further enhance their function, although the mechanisms are unknown. Recent studies suggest that transplanted stem cells primarily exert their effects through communicating with endogenous tissues via the release of exosomes containing cardioprotective molecules such as miRNAs, which upon uptake by recipient cells may stimulate survival, proliferation, and angiogenesis. Exosomes are also effective therapeutic agents in isolation and may provide a feasible alternative to stem cell transplantation. We hypothesize that EleS enhances CSC-mediated cardiac repair through its beneficial effects on production of cardioprotective exosomes. Moreover, we hypothesize that the beneficial effects of biventricular pacing in patients with heart failure may in part result from EleS-induced preconditioning of endogenous CSC to promote cardiac repair. With future research, our hypothesis may provide applications to optimize stem cell therapy and augment current pacing protocols, which may significantly advance the treatment of patients with heart disease.

Although thousands of potentially disease-causing mutations have been identified in a handful of genes, the genetic heterogeneity has led to diagnostic confusions, stemming directly from the limitations in our arsenal of genetic tools.We discuss the genetic basis of cardiac ion channelopathies, the gaps in our knowledge and how Next-generation sequencing technology (NGS) and can be used to bridge them, and how induced pluripotent stem cell (iPSC) derived-cardiomyocytes can be used for drug discovery.Univariate, arrhythmogenic arrhythmias can explain some congenital arrhythmias, however, it is far from a comprehensive understanding of the complexity of many arrhythmias. Mutational screening is a critical step in personalized medicine and is critical to the management of patients with arrhythmias. The success of personalized medicine requires a more efficient way to identify a high number of genetic variants potentially implicated in cardiac arrhythmogenic diseases than traditional sequencing methods (eg, Sanger sequencing). Next-generation sequencing technology provides us with unprecedented opportunities to achieve high-throughput, rapid, and cost-effective detection of congenital arrhythmias in patients. Moreover, in personalized medicine era, IPSC derived-cardiomyocytes can be used as 'cardiac arrhythmia in a dish' model for drug discovery, and help us improve management of arrhythmias in patients by developing patient-specific drug therapies with target specificity.

Disparities in atrial fibrillation (AF)-related stroke and mortality persist, especially racial disparities, within the US "Stroke Belt." This study identified barriers to optimal stroke prevention to develop a framework for clinician education. A comprehensive educational needs assessment was developed focusing on clinicians within the Stroke Belt. The mixed qualitative-quantitative approach included regional surveys and one-on-one clinician interviews. Identified contributors to disparities included implicit racial biases, lack of awareness of racial disparities in AF stroke risk, and lack of effective multicultural awareness and training. Additional barriers affecting disparities included patient medical mistrust and clinician-patient communication challenges. General barriers included lack of consistency in assessing stroke and anticoagulant-related bleeding risk, underuse of standardized risk assessment tools, discomfort with novel anticoagulants, and patient education deficiencies. Effective cultural competency training is one strategy to reduce disparities in AF-related stroke and mortality by improving implicit clinician bias, addressing medical mistrust, and improving clinician-patient communication.

Background Robust risk-adjustment algorithms are often necessary if data from clinical registries is to be used to compare rates of important clinical outcomes between participating centers. Although such algorithms have been successfully developed for surgical and catheter-based cardiac interventions in children, outcomes of pediatric and congenital catheter ablation have not been modeled with respect to case mix. Methods A working group was appointed by the Pediatric and Congenital Electrophysiology Society to develop a risk-adjustment algorithm for use in conjunction with a modernized, multicenter registry database. Expert consensus was used to develop relevant outcome measures, an inclusive list of possible predictors, and estimates of associated incremental risk. Historical data from the Pediatric Radiofrequency Ablation Registry was reanalyzed using multivariate regression to create statistical models of ablation outcomes. Results Acute ablation failure and serious adverse event rates were modeled as outcomes. Statistical modeling was performed on 4486 cases performed in 19 centers. For ablation failure rate, a simple model including general category of arrhythmia mechanism and presence of structural congenital heart disease accounted for ∼71% of outcome variance. The model was useful for identification of between-center variability in the historical data set. Although expert consensus predicted the need for a more complex model, predicted univariate effects were similar to those generated by statistical modeling. Serious adverse events were too infrequent to permit statistical association with any predictive variable, but could be compared with the mean rate observed among all centers. Conclusion A substantial component of the intercenter variability of acute ablation outcomes in a historical database of pediatric and congenital ablation patients may be accounted for by a simple statistical model, exposing variations in outcome specific to centers. This will be a useful initial model for use a modern registry for pediatric catheter ablation outcomes.

Amigo™ (Catheter Robotics, Inc., Mount Olive, NJ) remote catheter system (RCS) was designed to provide a simple and relatively inexpensive system for remote catheter manipulation. The purpose of this study was to evaluate the performance and safety of Amigo in mapping the right side of the heart. This non-randomized, prospective clinical trial was conducted at 13 sites (NCT: #01139814). Using the controller, a mapping catheter was moved to eight pre-specified locations in a specific sequence: right ventricular apex, mid-right ventricular septum, right ventricular outflow tract, His-bundle position, coronary sinus ostium, high right atrium, lateral tricuspid annulus, and low lateral right atrium. The pre-specified efficacy endpoint was to achieve 80 % successful navigation to all locations. Time to each location, location accuracy, and quality of contact were confirmed by imaging and specific criteria for electrograms and pacing thresholds. In 181 patients, a total of 1,396 of 1,448 (96 %) locations were successfully mapped with all protocol criteria met (one-sided p value

Transseptal catheterization of the interatrial septum has traditionally been performed under the guidance of fluoroscopy, echocardiography, and hemodynamic pressure monitoring. We hypothesized that the fossa ovalis could be identified on pre-ablation chest computerized tomography (CT) scan utilizing EnSite Verismo™ and Fusion™ software thereby permitting its real-time visualization during transseptal puncture. The purpose of this study is to generate multi-center data demonstrating the feasibility of the identification of the fossa ovalis and visualization of the transseptal needle tip using EnSite Verismo™ segmentation and EnSite Fusion™ prior to transseptal puncture. Patients scheduled to undergo transseptal puncture for ablation were enrolled. Pre-ablation CT scans were performed in all patients. The Verismo™ software tool was used to import and segmentally manipulate a three-dimensional CT image on the EnSite™ system workstation. EnSite Fusion™ registration was used to register the right atrial image and label and confirm the fossa ovalis’ location prior to transseptal puncture. Analysis of the pre-ablation CT scan using EnSite Fusion™ successfully allowed assessment of the anatomy and location of the fossa ovalis. Additionally, the transseptal needle tip location was located within the CT scan designated fossa ovalis location in 96% of cases. It is possible to visualize the fossa ovalis on pre-ablation CT and localize the transseptal needle accurately within the margins of the fossa ovalis utilizing EnSite Fusion™ and Verismo™ software.

With increasingly complex electrophysiologic procedures, particularly in patients with complex cardiovascular disease, the presence of an anesthesiologist in the electrophysiology lab has become more important. Anesthesiologists currently in training are likely to be involved in such procedures. This resource is intended to give anesthesia providers, including residents, medical students, and faculty, a better understanding of the basics of electrophysiologic procedures, the varied responses of both normal and abnormal myocardial tissue to volatile and intravenous anesthetic agents, and the anesthetic equipment required for the electrophysiology lab. This resource can be presented in 20 to 45 minutes, depending on the experience of the students. We have been able to successfully implement this program by using it as a training resource for faculty, residents, and medical students. For residents, training shortly before their scheduled time in the electrophysiologic lab will help to ensure retention of the information learned.

Hypoplastic left heart syndrome is a complex conglomerate of congenital cardiac abnormalities encountered in early life. Heart failure compensation and survival are intricately dependent on maintenance of ductal patency and avoidance of hyperoxic ventilation. While medical therapy is woefully inadequate, the staged Norwood procedure or cardiac transplantation remain the better options for treatment. Critically dependent on surgical outcomes, 5-year survival appears better with cardiac transplantation.

and repeated five times at 2-week intervals. T-wave morphology descriptors [TCRT, T-wave morphology dispersion (TMD) and CRA parameter] were calculated every 5 seconds in overlapping 10-second ECG segments. Recordings with fewer than total 1000 analyzable segments or fewer than 100 segments during the first or the last hour of the recording were excluded. Results: A total of 187 intradialytic recordings were included in the final analysis containing on average 2699 ± 592 ECG segments. Mean intradialytic values were as follows: CRA 0.204 ± 0.101, TMD 32.14 ± 21, and TCRT 0.282 ± 0.583.There was a positive correlation between CRA and TMD (p = 0.000, CE .528) and CRA and TCRT (0.312, p = 0.000). Comparison between averaged values during the first and after the third hours of recordings showed statistically significant differences in CRA, TCRT and TMD [independent-sample t test p b 0.05 for 182 (97.3%), 179 (95.7%) and 180 (96.3%) of comparisons respectively]. Intradialytic changes were expressed as (last hour value − first hour value)/first hour value and denoted as CRAD, TMDD and TCRTD. More than 10% intradialytic increase was noted in 55.5%, 41.8 %, and 55.5% while more than 10% decrease in 8.2%, 35% and 12.3% of the overall recordings for CRA, TCRT and TMD, respectively. There was a positive relationship between intradialytic change of CRA and TMD (correlation coefficient of 0.211, p = 0.05). Repeated-measures ANOVA of average CRA, TMD, TCRT and their intradialytic changes (CRAD, TMDD and TCRTD) in subjects with five consecutive analyzable recordings showed intrasubject stability (CRA F = 0.558, p = 0.694; TMD F = 0.770, p = 0.483; TCRT F = 1.966, p = 0.135; CRAD F = 0.356, p = 0.839; TMDD F = 0.533, p = 0.630; TCRTD F = 1.498, p = 0.239). Pre-dialysis hyponatremia was associated with higher intradialytic changes in CRA (independent-sample t test p = 0.019). Conclusion: T-wave morphology descriptors exhibit differential subject specific dynamic profiles in response to fluid and electrolyte changes on dialysis. Predialysis hyponatremia may have a role in intradialytic CRA changes.